Steganography, the process of concealing secret messages in other plain messages, can be used to encode secret data, and protect digital assets (e.g., against data piracy). In the digital era, steganographic techniques have been applied to digital image, video, and audio data. However, use of digital text steganography is generally considered more challenging than its counterparts for image, video, and audio data. This is because the “pixel” of a text document is its individual letters, which, unlike an image pixel, cannot be changed into other letters without causing noticeable differences.